[unreadable] [unreadable] This is a defining moment in the 50-year history of cardiac surgery. For 30+ years, the specialty has been dominated by coronary artery bypass grafting (CABG). Percutaneous coronary intervention has largely replaced CABG as the initial treatment of coronary artery disease, making cardiac surgery a treatment of last resort for patients with complex heart disease. In redefining itself, an atmosphere of innovation abounds, but secure evidence for clinical application of new therapies lags behind enthusiasm. A Network of high-volume Clinical Centers, poised to perform proof-of-concept clinical trials and establish registries, is needed now as never before. Cleveland Clinic, America's highest-volume, highest-ranked cardiovascular surgery program, with the largest clinical research group, possesses the desire, capacity, capability, and track record to participate fully in this Network as a Clinical Center and Clinical Research Skills Development Core. We propose 2 randomized trials of new therapy. One represents the first of several needed steps in testing surgical ablation of permanent atrial fibrillation accompanying structural heart disease in need of surgical intervention. It will test the hypothesis that a more extensive, biatrial lesion set more effectively prevents recurrent atrial fibrillation than simple pulmonary vein isolation. The second tests the hypothesis that newly emerging endovascular exclusion of chronic distal aortic dissection that has undergone aneurysmal degeneration is safer than open surgery. We also propose a clinical research skills development core built on our existing successful Roadmap K12 multidisciplinary scholars program, targeting 1 full-time cardiovascular surgeon-scholar per year for a 2- year education and mentored research fellowship. Lay Summary: The specialty of cardiac surgery needs redirection, with innovation coupled with rigorous multicenter testing of new therapies to be certain of their value. We present 2 randomized trials: 1 tests new treatments for a common heart rhythm disturbance that causes strokes and death, and the other tests a new, less invasive therapy for a disease of the aorta that unexpectedly causes people to bleed to death. We also propose to educate and mentor new surgeon-investigators to take a leadership role in devising ways to build an evidence basis for use of innovative therapies in patients with life-threatening heart disease. [unreadable] [unreadable] (End of Abstract) [unreadable] [unreadable] [unreadable]